Liquid fuel pumps



July 27, 1965 D. A. CHANNlNG ETAL LIQUID FUEL PUMPS 5 Sheets-Sheet 1Filed April 2, 1965 y 7, 5 D.IA.CHANNING ETAL 3,196,796

Filed April 2 y 7. 1965 D. A. CHANNING ETAL. 3,196,796

LIQUID FUEL PUMPS 5 Sheets-Sheet 5 Filed April 2, 1963 July 27, 1965 In; A. CHANNING ETAL 3, ,7

LIQUID FUEL PUMPS Filed April 2, 196a 5 Sheets-Sheet 4 July 27, 1965Filed April 2, 1963 D. A. CHANNING ETAL LIQUID FUEL PUMPS 5 Sheets-Sheet5 United States Patent 3,196,796 LEQUID FUEL PUMP Derelr Albert(Ihanning, Shepherds Bush, London, and

Kenneth Albert Walters Kemp, Ealing, London, England, assignors to CAN.Limited, Acton, London, England Filed Apr. 2, 1963, Ser. No. 276,018 3Claims. (Cl. ll3--2) This invention relates to liquid fuel pumps forinternal combustion engines, more particularly compression ignitionengines, and of the kind comprising an injection pump including aplunger engaging a bore in which it is arranged to be moved inwardlythrough an injection stroke by the action of a cam, and in which it ismoved outwardly by the pressure of the fuel fed thereto from a feed pumpduring a filling stroke, in combination with a rotary distributorthrough which fuel can be fed alternately to the bore, and from the boreto the engine cylinders in turn, in timed relationship to an engine withwhich the pump is associated.

The object of the invention is to provide such a pump in a convenientform.

According to the invention a pump of the kind specified has incombination a cylinder, a shuttle axially movable in the cylinder,passages in the distributor through which fuel can flow from the feedpump to one end of the cylinder to move the shuttle in one direction todisplace fuel from the other end of the cylinder to a source at lowerpressure whilst the injection pump is partaking of an injection stroke,and whereby fuel can flow from the feed pump to said other end of thecylinder to move the shuttle to displace fuel from said one end of thecylinder to the bore of the injection pump during the filling stroke,and a means for controlling the amount of fuel flowing to and/ or fromsaid other end of the cylinder.

In the accompanying drawings.

FIGURE 1 is a sectional side elevation of one example of a liquid fuelpump for supplying fuel to a four cylinder internal combustion engine.

FIGURES 2, 3, 4, are sections on the line 2--2, 33, 44 of FIGURE 1respectively.

FIGURE 5 is a view similar to FIGURE 1 with parts of the pump in anotherposition.

FIGURES 6, 7, 8 are sections on the lines 66, 77, 8-8 of FIGURE 5respectively.

FIGURE 9 is a sectional side elevation of a modification of the pumpshown in FIGURE 1.

FIGURE 10 is a view similar to FIGURE 9 with part of the pump in anotherposition and FIGURES 1-1 and 12 are sections on the lines 11I-1, I2I2 ofFIGURE 9 respectively.

Referring to the drawings there is provided a body part 1 which at oneend contains a feed pump 2 having an inlet 3 and outlet 4- in the bodypart.

At the other end of the body part there is provided an injection pumpwhich includes a rotary head 5 having formed in its a transverse bore 6.The bore extends diametrically through the head and contains a pair ofreciprocable plungers 7. As the head rotates both plungers are movedinwardly at an appropriate time by the interaction of rollers 7a attheir outer ends with a surrounding annual cam 7b.

The rotary parts of the feed and injection pumps are interconnected by acylindrical distributor 8 and are adapted to be driven as a unit througha coupling 9 by the engine with which the pump is associated. In thedistributor S is formed an axial passage 10 which at one end is incommunication with the bore 6 and which at its opposite end is incommunication with a radial outlet 3,196,796 Patented July 27, 1965passage 11 formed in the distributor. The outlet passage communicates asthe distributor rotates with each in turn of four equi-angularly spacedoutlet ports 12 in the body part, the outlet ports being incommunication with four injection nozzles (not shown) associated withthe four cylinders of the engine respectively.

Within the distributor are four equi-angularly spaced radial inletpassages 13 in communication at their inner ends with the axial passage10. The outer ends of the inlet passages are arranged to communicate inturn With an inlet port 14 in the body part as the distributor rotates.Also provided in the distributor are a pair of circumferentiallyextending grooves, 15, 16 each groove communicating respectively withfour associated equi-angularly spaced longitudinally extending grooves17, 18 formed in the periphery of the distributor. The firstcircumferential groove 15 is arranged to be in communication at alltimes with the outlet 4 of the feed pump via a passage 19 within thebody part and the longitudinally extending grooves 17 are adapted toregister in turn with the aforementioned inlet port 14 as thedistributor revolves. The circumferential groove 16 is at all timesarranged to be in communication with a port 20 in the body part, and thelongitudinally extending grooves 18 are adapted to register alternatelyand in turn with the passage 19 and the feed pump inlet via passages 21and 22, as the distributor rotates.

As an alternative (shown in FIGURE 9) the longitudinally entendinggrooves 13 may communicate in turn with a space formed around the headof the injection pump through a passage 18b the space being incommunication with the feed pump inlet.

Within the body part there is provided a cylinder 23 extending radiallyrelative to the distributor, and having slidably mounted therein ashuttle 24. The inner end of the cylinder is in communication with theaforementioned inlet port 14, and the outer end of the cylinder is incommunication with the circumferential groove 16 through a throttle.

The trottle may take the form of a cylindrical valve member 25 engagingthe outer end portion of the cylinder, and having formed therein alongitudinal groove 26 with a helical edge. The valve member isangularly movable about its axis either manually or by a governor, andthe arrangement is such that its angular setting determines the quantityof fuel which can flow to, and from the cylinder to the port 20 throughthe groove 26.

Moreover, the axial position of the valve member in the cylinder isdetermined by an externally adjustable stop 27 which limits the axialmovement of the valve member by the pressure of fuel. Since the axialposition of the valve member determines the permitted movement of theshuttle the stop 27 provides an adjustable setting of the maximum amountof fuel which can be delivered by the pump.

The operation of the pump will now be described. Assume that the pump isfilled with fuel and the injection period is just starting. The plungers7 are moved inwardly by the interaction of the rollers 7a on the annularcam 7b and fuel is displaced along the axial passage 10 to the outletpassage Ill and thence to one of the four outlet ports 12. At the sametime fuel is admitted to the inner end of the cylinder, from the feedpump outlet passage via the circumferential groove 15, one of thelongitudinally extending grooves 17 and the inlet port 14-. This fuelforces the shuttle 24 outwards in the cylinder. The fuel displaced fromthe outer end of the cylinder flows via the groove 26 in the valvemember 25 to the circumferential groove 16, along one of thelongitudinally extending grooves to the passage 21, or 22 in thealternative to the space around the head of the injection pump via thepassage 181;. When the distributor has moved through a predeterminedangle of, for example, 45 the plungers 7 are forced outwardly in thefollowing manner. Fuel from the feed pump outlet 4 flows by way of thepassage 19, one of the longitudinally extending grooves 18, thecircumferential groove 16 and the groove 26 in the valve member 25 tothe outer end of the cylinder 23. The shuttle 24 is moved inwardly andfuel is displaced from the inner end of the cylinder via the inlet port14, one of the inlet passages 13 and the axial passage to move theplungers outwardly. When the distributor has moved through a further 45another injection period commences and the cycle is repeated.

It will be appreciated that the action of the groove 26 in the valvemember is to limit the displacement of the shuttle and so reduce theoutward movement of the plungers. The maximum permissible displacementof the shuttle 24 is limited by its outer end abutting against the innerend of the valve member so that even if the valve member is angularlyset to permit maximum flow of the fuel entering and leaving the outerend of the cylinder, the maximum amount of fuel which can be supplied tothe engine is controlled by the axial setting of the valve member andhence by the stop.

In the modification shown in FIGURE 9 onwards the fuel flows into theouter end of the cylinder 23 by way of a radial passage 28 in the bodypart which at its inner end is in communication, at the appropriatetime, with one of the longitudinally extending grooves 18 and at itsouter end is in communication with the outer end of the cylinder at aposition to by-pass the throttle. Thus it is only the fuel displacedfrom the outer end of the cylinder which is throttled.

If desired and as shown in FIGURES 2, 6, 9, 10 and 11 an excess fuelvalve may be provided comprising a valve member 29 arranged, when open,to permit fuel to bypass the shuttle 24 and flow directly from the outerend of the cylinder through one of the passages 13 to the bore 6 in thehead to permit the plungers to move out to their maximum extents, aspermitted by the cam, so that when they are moved inwardly again as thedistributor rotates an excess quantity of fuel will be delivered to theengine.

Having thus described our invention what we claim as new and desire tosecure by Letters Patent is:

1. Liquid fuel pumping apparatus comprising, in combination a stationaryhollow body, a feed pump at one end of the body and having a fuel inletand a fuel outlet therein, a rotary head at the other end of the bodypart, said head having formed in it a bore, a reciprocable plungerwithin the bore, a cam mounted in the body and arranged to move theplunger inwardly as the head rotates, a rotary distributor within thebody, said distributor connecting the feed pump and the head, alongitudinal passage within the distributor in communication with thebore in the head, a plurality of equi-angularly spaced inlet passages inthe distributor extending outwardly from said longitudiin turn, as thedistributor rotates with said inlet port to allow fuel from the outletof the feed pump to move the shuttle axially away from said one end ofthe cylinder, a further port in the body in communication with saidother end of the cylinder, a second series of equi-angularly spacedlongitudinal grooves in the periphery of the distributor incommunication at all times with said further port and arranged to beplaced in communication alternately, and in turn, with the feed pumpoutlet and the feed pump inlet to move the shuttle towards said one endof the cylinder during the time when the inlet port is in register withone of the inlet passages so as to displace 7 fuel to the bore in thehead, and whereby when the inlet port is in register with one of saidfirst series of grooves fuel from said other end of the cylinder will bedisplaced to the feed pump inlet, a valve member axially slidable in theother end of said cylinder and angularly movable relative to the body, ahelical groove formed on the periphery of said valve member forco-operation with said further port to control the rate at which fuelflows therethrough, said valve member also serving as a stop to controlthe permitted axial movement of the shuttle.

2. A liquid fuel pump according to claim 1 incorporating a further valvemember in the body said valve member being operable to allow fuel fromthe outlet of the feed pump to be fed directly to the bore in the headduring the time when the inlet passages are in register with the inletport.

3. Liquid fuel pumping apparatus comprising in combination, a stationaryhollow body, a liquid fuel injection pump mounted within the hollow bodyand having a rotary driving member, a rotary distributor mounted in thehollow body and rigid with the driving member of the injection pump, aplurality of outlets formed in the body,

passages in the rotary distributor and hollow body for conveying fuelfrom the injection pump to each in turn of the outlets, a fuel supplyport located within the body said supply port being connectable to asource of fuel 7 under pressure, a cylinder in the hollow body, ashuttle nal passage, an inlet port in the body with which said inletpassages are arranged to communicate, in turn, as the distributorrotates, a delivery passage in the distributor extending outwardly fromsaid longitudinal passage, a plurality of equi-angularly spaced deliveryports in the body and with which the delivery passage is incommunication, in turn, as the distributor rotates during the time whenthe plunger is moved inwardly by the cam, a cylinder within the body,one end of said cylinder being in communication with said inlet port, ashuttle axially movable within the cylinder, a first series ofequi-angularly spaced longitudinal grooves in the periphery of thedistributor, said first series of grooves being in communication at alltimes with the outlet of the feed pump and arranged to register,

axially movable in the cylinder, further passages in the distributor forestablishing communication between said supply port and one end of saidcylinder to move the shuttle in one direction thereby displacing fuelfrom the other end of said cylinder during the time when the injectionjump is delivering fuel to an outlet, and whereby the supply port isplaced in communication with said other end of the cylinder to move theshuttle in the other direction to cause fuel to be displaced from oneend of said cylinder to the injection pump during the filling period ofthe latter, an axially adjustable plug mounted in said other end of thecylinder for controlling the permitted excursion of the shuttle saidplug being provided with a throttling groove whereby the rate at whichfuel flows from the supply port to the cylinder is adjustable to controlthe quality of liquid fuel delivered through the outlet ports.

References Cited by the Examiner UNITED STATES PATENTS 2,946,292 7/60Chmielecki 103-2 1 2,989,003 6/61 Evans 103--2.1 3,025,797 3/62 Hutchson103-21 3,035,523 5/62 Kemp et al. 1032.1 3,058,425 10/62 Evans 103-2.13,101,079 8/63 Evans 103-21 3,107,661 10/63 Kemp 123139.1l

MARK NEWMAN, Primary Examiner.

LAURENCE V. EFNER, RICHARD B. WILKINSON,

Examiners.

1. LIQUID FUEL PUMPING APPARATUS COMPRISING, IN COMBINATION A STATIONARYHOLLOW BODY, A FEED PUMP AT ONE END OF THE BODY AND HAVING A FUEL INLETAND A FUEL OUTLET THEREIN, A ROTARY HEAD AT THE OTHER END OF THE BODYPART, SAID HEAD HAVING FORMED IN IT A BORE, A RECIPROCABLE PLUNGERWITHIN THE BORE, A CAM MOUNTED IN THE BODY AND ARRANGED TO MOVE THEPLUNGER INWARDLY AS THE HEAD ROTATES, A ROTARY DISTRIBUTOR WITHIN THEBODY, SAID DISTRIBUTOR CONNECTING THE FEED PUMP AND THE HEAD, ALONGITUDINAL PASSAGE WITHIN THE DISTRIBUTOR IN COMMUNICATION WITH THEBORE IN THE HEAD, A PLURALITY OF EQUI-ANGULARLY SPACED INLET PASSAGES INTHE DISTRIBUTOR EXTENDING OUTWARDLY FROM SAID LONGITUDINAL PASSAGE, ANINLET PORT IN THE BODY WITH WHICH SAID INLET PASSAGES ARE ARRANGED TOCOMMUNICATE, IN TURN, AS THE DISTRUBUTOR ROTATES, A DELIVERY PASSAGE INTHE DISTRIBUTOR EXTENDING OUTWARDLY FROM SAID LONGITUDIBAL PASSAGE, APLURALITY OF EQUI-ANGULARLY SPACED DELIVERY PORTS IN THE BODY AND WITHWHICH THE DELIVERY PASSAGE IS IN COMMUNICATION, IN TURN, AS THEDISTRIBUTOR ROTATES DURING THE TIME WHEN THE PLUNGERR IS MOVED INWARDLYBY THE CAM, A CYLINDER WITHIN THE BODY, ONE END OF SAID CYLINDER BEINGIN COMMUNICATION WITH SAID INLET PORT, A SHUTTLE AXIALLY MOVABLE WITHINTHE CYLINDER, A FIRST SERIES OFF EQUI-ANGULARLY SPACED LONGITUDINALGROOVES IN THE PERIPHERY OF THE DISTRIBUTOR, SAID FIRST SERIES OFGROOVES BEING IN COMMUNICATION AT ALL TIMES WITH THE OUTLET OF THE FEEDPUMP AND ARRANGED TO REGISTER, IN TURN, AS THE DISTRIBUTOR ROTATES WITHSAID INLET PORT TO ALLOW FUEL FROM THE OUTLET OF THE FEED PUMP TO MOVETHE SHUTTLE AXIALLY AWAY FROM SAID ONE END OF THE CYLINDER, A FURTHERPORT IN THE BODY IN COMMUNICATION WITH SAID OTHER END OF THE CYLINDER, ASECOND SERIES OF EQUI-ANGULARLY SPACED LONGITUDINAL GROOVES IN THEPERIPHERY OF THE DISTRIBUTOR IN COMMUNICATION AT ALL TIMES WITH SAIDFURTHER PORT AND ARRANGED TO BE PLACED IN COMMUNICATION ALTERNATELY, ANDIN TURN, WITH THE FEED PUMP OUTLET AND THE FEED PUMP INLET TO MOVE THESHUTTLE TOWARDS SAID ONE END OF THE CYLINDER DURING THE TIME WHEN THEINLET PORT IS IN REGISTER WITH ONE OF THE INLET PASSAGES SO AS TODISPLACE FUEL TO THE BORE IN THE HEAD, AND WHEREBY WHEN THE INLET PORTIS REGISTER WITH ONE OF SAID FIRST SERIES OF GROOVES FUEL FROM SAIDOTHER END OF THE CYLINDER WILL BE DISPLACED TO THE FEED PUMP INLET, AVALVE MEMBERS AXIALLY SLIDABLE IN THE OTHER END OF SAID CYLINDER ANDANGULARLY MOVABLE RELATIVE TO THE BODY, A HELICAL GROOVE FORMED ON THEPERIPHERY OF SAID VALVE MEMBER FOR CO-OPERATION WITH SAID FURTHER PORTTO CONTROL THE RATE AT WHICH FUEL FLOWS THERETHROUGH, SAID VALVE MEMBERALSO SERVING AS A STOP TO CONTROL THE PERMITTED AXIAL MOVEMENT OF THESHUTTLE.